This invention relates to machines for assembling and fastening forms in shingled sets, and more particularly to a machine which is especially adapted for rapidly and continuously numbering, assembling, and fastening forms from a continuous web thereof into shingled sets of predetermined count. The forms in each set are numbered with related, usually identical numbers, while the number printed on the forms in one set differs from that on any other set.
Such shingled sets of forms, often called "controlled" sets, are becoming increasingly popular. The positive numbering of the forms provides for precise control and accounting for every form which is issued. For example, such sets are used in hospitals in connection with controlled substances such as narcotics. A certain initial quantity of the substance may be "assigned" to a given set of the forms (for instance 20 forms), and each time a dose of the substance is administered, a precise record is entered on one of the forms in the set. The shingled forms are usually attached to the front of a large receipt or control ledger onto which the information entered on the individual sheets or forms is copied. Further, that initial quantity of the controlled substance, and the corresponding particular controlled set of forms, become the responsibility of one individual (for example, a particular nurse). Thus "phantom" forms, perhaps stolen from a supply room, cannot be used to obtain unauthorized material because the forms are numbered and identifiable.
In prior art shingling machines, the individual forms are commonly supplied in stacks of discrete sheets which have been pre-numbered in groups of predetermined count. The forms in each group have identical numbers so that they can be shingled into corresponding sets as described. The stacks are prepared in several phases, each of which requires operator intervention, thereby interrupting the continuity of the preparation thereof. For example, a printing press may typically be equipped with a sheeter to separate the individual forms from the continuous web as it comes out of the printing press. The stacks of individual sheets are then transferred to another machine where they are numbered in their groups and re-stacked. These in turn are transferred to and fed into a sheet shingling machine.
It might be thought that the forms could be directly numbered on the printing press itself. Prior experience, however, has shown that as a practical matter this is mechanically too difficult. It is true that consecutive numbering is commonly done in which each form is numbered one higher than the last. This is an entirely different matter, however, from numbering the forms in groups in which the forms in each group receive identical or related numbers.
Known numbering presses which number consecutively have press speeds, for example, of 500 feet per minute, which is substantially slower than presses which do not require printing this variable information. Every time such a press is started, there are potential registration problems between the fixed information and the printing of the variable (number) information. Further, every time one roll is spliced to another (which is usually done while the press continues operating at or near full speed), a form must be rejected due to the splice therein. Also, the individual rolls themselves commonly have one or two mill splices in them, leading to additional rejected forms.
These problems are serious enough on presses which number consecutively. In the preparation of controlled sets, in which exact numbers of splice-free forms must be provided, it is impractical to try to number these forms on the initial printing press. The frequent interruptions and restarting which would be occassioned by the splices would be intolerable. Not unimportant, also, is the lack of numbering equipment which can satisfactorily advance intermittently (for example, once every twenty forms) at these press speeds.
A need therefore remains for a method and apparatus compatible with continuous full speed operation of printing presses for the production of controlled sets of shingled forms. Preferably, such a method and apparatus will allow the individual forms as they first come from the printing press to be rewound onto a roll at full speed, as a continuous web, rather than requiring the web of forms to be fed more slowly directly into a sheeter. Then, in a single operation, these rolls should be transferable to a machine which, in a unitary apparatus, will number and process the forms into the shingled, overlapped, controlled sets.